Question

Math help. PLS help.

Answer 1

http://prnt.sc/abew9p

Answer 2

@hartnn

Answer 3

can you find sin (7pi/6) ??

hint:
sin x = - sin(pi -x)

Answer 4

how is sin negative?

Answer 5

oops,

sin x = sin (pi -x)

Answer 6

you can take x = 7pi/6 here

Answer 7

what is pi-x?

Answer 8

\(\pi -x\)

Answer 9

isnt 7pi/6 = 1/2?

Answer 10

sin 7pi/6 is -1/2 not +1/2

Answer 11

then just square both sides

Answer 12

why is 7pi/6 = -1/2??

Answer 13

\(\sin 7\pi/6 = \sin (\pi -7\pi/6) = \sin(-\pi/6) = -\sin(\pi/6) = -1/2\)

Answer 14

i dont get it

Answer 15

you keep on saying 7pi/6 = 1/2...
note that 7pi/6 is an angle,
1/2 is a number.
we can't equate them.

sin 7pi/6 is a number
which is = -1/2 as i have shown

Answer 16

we have used this property
\(\sin x = \sin (\pi -x)\)
and just plug in x = 7pi/6 therwe

Answer 17

ohh ok what about cos then?

Answer 18

@hartnn

Answer 19

you mean cos 7pi/6?

Answer 20

the formula for finding the value for cos